Police are searching for a shooter who opened fire at the Washington Navy Yard, the military and multiple news agencies have confirmed on Twitter.
Several people have been injured, according to the DC Fire Union.
The U.S. Navy alerted Twitter users that there are "reports of fatalities," and the Navy is reporting that at least 10 people were injured Monday morning.
MSNBC reports that a naval security guard was among those shot.
The suspect was reportedly inside the Naval Sea Systems Command Headquarters building at 8:20 a.m. About 3,000 people work in the building.
Several news outlets have said that he has barricaded himself inside a particular room, but police haven't confirmed or denied that particular report.
The suspect is described as a black male with a dark complexion, approximately 5-foot-10 to 6 feet tall, 170 pound with a black shirt and a black hat.
He is believed have multiple guns, including an AR-15.
A "shelter in place" order has been issued for Navy Yard personnel. At least six schools were on lockdown as a precaution in the D.C. area, CNN reports.
SWAT crews and police from multiple local and federal agencies are on the scene. President Obama has been briefed "several times" about the shooting.
UPDATE: At least seven people have reportedly died, according to the Washington Post, with as many as three shooters responsible for the carnage.
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